Research suggests that 4 - 23% of the seriously mentally ill (SMI) are infected with the human immunodeficiency virus (HIV). The long-term aim of the proposed research is to reduce the prevalence of HIV infection among SMI adults who receive outpatient psychiatric care. The specific aims are (1) to conduct formative research regarding HIV-related risk behavior among the SMI; (2) to refine, implement, and evaluate an HIV-risk reduction program with the SMI; and (3) to use Fisher and Fisher's (1992) Information-Motivation-Behavioral Skills model to account for variability in HIV-related risk behavior in the SMI. The proposed research begins with 6 months of formative research; focus groups and individual qualitative interviews will be conducted with 25 men and 25 women. Based upon prior pilot and proposed formative work, a theoretically-based, culturally- and clinically-sensitive, HIV risk reduction intervention for the SMI will be implemented with 216 men and 216 women. Participants will be randomly assigned to (a) an HIV Risk Reduction program (HIV), (b) a Substance Use Reduction (SUR), or (c) a Standard Care (Control) Condition. Assessments made at baseline, post-intervention, and at 3- and 6-month follow-ups will measure HIV-related information, motivation, behavioral skills, and sexual practices. We hypothesize that, relative to participants assigned to the SUR and Control conditions, participants in the HIV intervention will increase HIV-relevant (a) information, (b) motivation, (c) behavioral skills; and decrease (d) the frequency of risky sexual practices. We hypothesize further that (e) participants in the HIV condition will redeem coupons for condoms and seek voluntary HIV-antibody testing at a greater rate than will participants in the SUR and Control conditions; (f) independent of treatment condition and substance use behavior, HIV preventive behavior at time n + 1 (e.g., 3-month follow-up) will be a function of individuals' information about the transmission and prevention of HIV infection, motivation to engage in HIV prevention, and behavioral skills for performing the specific acts involved in prevention at time n (e.g., post-test); and (g) information and motivation will be mediated by behavioral skills to influence preventive behavior. The intent of this research is to develop a risk reduction program that can be used by community-based mental health organizations to reduce the risk of HIV infection among the SMI.